Sony e 35mm f 1.8 oss đánh giá năm 2024
I knew I would come around eventually to buying an autofocus lens for the NEX system. The only problem was that all the autofocus lenses that have been released up to now from Sony have been zooms (large and/or slow apertures), primes with “O.K.” image quality (16mm f/2.8, 30mm f/3.5 macro), lenses I already have focal lengths well covered for (50mm f/1.8 OSS), or crazily overpriced optics (Zeiss 24mm f/1.8). Show What I was waiting for was a cheap(er), high performing lens that would give great performance at most settings in a small a package as possible—in other words, one that fit with NEX shooting style. Well, it seems Sony has finally done it, releasing their new 35mm f/1.8 for E-mount. With the field of view of 52.5mm in 35mm format, this is the only first-party “standard” solution for the camera apart from using their alpha-mount lenses via a relatively bulky adapter. At $450, it’s not cheap, either. In fact, in my first impressions of the lens, I had my doubts as to whether or not Sony was deliberately price-gouging when compared to the Nikon/Canon equivalents. But a few of my readers brought up great points. Not only does optical stabilization make lenses more expensive than I thought (looking at Canon’s brand-new 35mm f/2 IS), but I am totally incorrect in comparing an SLR lens to a mirrorless lens. With their inherent design differences—mainly, working with a MUCH shorter flange distance—it simply costs more to design compact lenses that cover a whole APS-C sensor without severely compromising optical quality. Instead, the 35mm f/1.8 should be compared to fellow mirrorless equivalents. A couple to look at, the Panasonic/Leica 25mm f/1.4 and the Fuji 35mm f/1.4 XF R. All three lenses have essentially the same field-of-view, and are close in aperture speed (the Sony only 2/3 a stop slower). The Panasonic/Leica lens runs at about $500, while the Fuji is a whopping $600. Seeing as neither have optical stabilization, the $450 asking price of the 35mm f/1.8 could be argued to be the better deal! But a cheap(er) lens shouldn’t merit praise on its own, does the 35mm f/1.8 stand up to the power of the NEX-7’s huge 24MP sensor? Let’s take a look! SpecificationsFull Name: Sony E 1.8/35 OSS Dimensions: 2.5 inches/63mm in diameter, 1.77 inches/45mm long without hood, 2.75 inches/70mm long with hood, with a feather-weight of only 5.5 ounces/155 grams (hood may add another ounce or so) Close-Focus: Marked at .98 feet/.3 meters, you cannot get any closer Miscellaneous: 7-bladed quasi-circular aperture stopping down to f/22, 49mm filter thread, large ribbed “fly-by-wire” focus ring, internal focusing with no rotation of filter thread, metal mount, metal barrel, plastic hood, plastic filter thread, excellent pinch-type lens cap, all-black finish blends well with black NEXes (but dust/grime shows up very easily…) The “Feel”The Sony 35mm f/1.8 is designed to be a do-it-all “standard”, compact, walk-around lens; the way it shoots really exemplifies this. The lens sports a metal finish (and mount), but the hood, filter thread, and probably much of the internals are plastic. This helps the tiny optic feel great in the hand and on the camera. Since the camera itself (NEX-7) is over twice the weight of the 35mm f/1.8, it comfortably rear-balances towards the grip. With the total package hovering around the one-pound mark, one-handed shooting is a cinch. Using the flexible spot (and turning off the troublesome AF “assist” light), autofocus was generally very accurate and pretty speedy on static subjects in most conditions. However, the lens consistently failed to properly focus on high-contrast objects, such as ice on a branch, typically back-focusing heavily. It is in these situations that the 35mm f/1.8 is extremely troublesome to use. Since the focusing mechanism is electronic “fly-by-wire”, going from close-focus to infinity or vice-versa manually can take well over 10 seconds—even when turning the ring fast (meaning, getting macro shots is a real pain). Also, this system has a hard time judging minute focusing movements. When trying to ever-so-slightly change focus (such as acquiring critical focus on test charts), the lens would sometimes refuse to focus (moving the ring too slow), or jump way past where it needed to be (too fast). I NEVER have this problem with any of my Nikkors, where I can—at the same time—go from macro to infinity in the flick of a wrist and make minute adjustments to the focus point with tiny rotations. I do know that this isn’t an issue specific to the 35mm f/1.8, rather, is found in ALL E-mount (and most mirrorless-system) lenses, but it doesn’t make it any less frustrating the times it crops up in photography. Another CDAF-specific focusing problem, the 35mm f/1.8 has a very difficult time focusing on moving objects. The faster the subject moves, the less accurate it will be, regardless if using AF-S or AF-C. I tested out the focusing of a horse cantering around a trainer in a circle. In all the various settings I attempted (AF-S, AF-C, multi-point, center flexible spot, change of aperture), autofocus largely missed focus, almost trailing behind the subject. The only tactic that helped was stopping down a bit, undoubtedly because of the depth-of-field increase. Rare-focusing issues aside, can the 35mm f/1.8 excel in my four pillars of shootability?
PerformanceSummaryI have read some reports that the 35mm f/1.8 is ever-so-slightly better than Sony’s own 35mm f/1.8 in alpha-mount. Seeing as that APS-C lens has always gotten much praise, with many photographers using the lens on their NEX’s, this E-mount lens is a stellar performer in most aspects. I wouldn’t hesitate to recommend it to any NEX photographer looking for a fast “normal” lens, with only minor caveats (discussed below). SharpnessStarting with center sharpness, here are some 100% crops arranged top-to-bottom by aperture. As a side note, I did remember to turn OSS off so it didn’t introduce rouge lens element vibrations in the tests: Wide-open at f/1.8, detail is hidden from spherical aberration, and—at the pixel level—can be taken as “soft”. Only one stop down (oh okay, a stop and a third, technically) at f/2.8, detail is very sharp. At f/4, center detail has already peaked! F/5.6 is essentially the same, while diffraction sets in noticeably by f/11, dulling detail and contrast. Speaking of contrast, though peaking at f/2.8, it is maintained very well throughout the f/1.8-11 aperture range. Now onto some corner crops:Seeing as this is the first E-mount lens I have tested that I know for certain is designed for an APS-C sensor only (still not sure about the Noktor HyperPrime), I wasn’t looking forward to the corner performance. Many reviews of NEX APS-C lenses on the demanding NEX-7 sensor show that corners smear and are much lower in detail than when those same lenses are used on less-megapixel-dense cameras such as the NEX-C3/F3/5n/5r/6. Much to my surprise, corners do a pretty good job here, all things considered. Spherical aberration and vignetting hides detail at f/1.8. Corners are still a bit soft by f/2.8, but they eventually sharpen up to a good degree by f/5.6 where detail peaks. Diffraction noticeably sets in, as in the centers, at f/11. Unfortunately, looking at the center and corner crops side-by-side, I can easily see that the corners never do get as nice and sharp as the centers do. F/5.6 in the corners looks closer to f/16 in the centers. With these test results, I first thought to not recommend the 35mm f/1.8 as a critical landscape lens on the NEX-7. However, my infinity sharpness test tells a starkly different story. Also, keep in mind that corners in mid- to close-range photography at f/1.8-4 probably won’t be in focus anyway.On a side note, I see little to no focus shift or field curvature with the 35mm f/1.8. Great! Electrical Symmetry 35mm, ISO 100, f/1.8, 1/250 Admittedly, stopping down some here would have helped sharpen things up, though with some adjustments to sharpness and clarity in post, files can still “pop” across the frame even wide-open. Sharpness at InfinityTo assess how the 35mm f/1.8 may perform as a landscape lens (since the test charts were focused at a relatively close 2 feet), I shot this uninspiring landscape with a very far-off house/mansion(?): 100% crops taken from the small little building in the center of this shot. I took this late in the day to try to avoid any heat shimmer, which robs sharpness at infinity more than any lens’ resolving ability Personally, I am quite surprised at the difference in sharpness at infinity versus sharpness in the “controlled” environment of shooting a test chart. At infinity, a photographer can easily get across-the-frame sharpness at about f/5. Though one may be able to squeeze a bit more corner sharpness at infinity using a less megapixel-dense camera, the 35mm f/1.8 does a fantastic job in the corners of the resolution-monster NEX-7. However, if you are looking for a clinically-sharp lens from corner to corner, check out the Sigma 30mm f/2.8. I do not own the lens, nor have I shot with it, but the multitude of tests on this little gem around the internet show astounding results for sharpness as a landscape lens—especially on the NEX-7. The Flame Lighting Up the Sky 35mm, ISO 100, f/3.2, 1/100 (Not true infinity focus, but pretty close!) Sharpness at MacroThe 35mm f/1.8 has the nice ability to focus to a close .98 feet/.3 meters. This is about the same distance as a lens I called the “poor man’s macro” when I reviewed the Nikon 35mm f/2.5 E. For such a compact lens, I’m glad to see the 35mm f/1.8 capable of general macro work, such as medium-sized flowers. The perspective of using a relatively wide-angle lens (compared to a 50mm/105mm/180mm dedicated macro lens) makes macro subjects seem larger. As close as you can get In this 100% crop at f/5.6, detail is excellent and contrast is high To etch out a little bit more sharpness across the frame, stop down to f/8. Just Hanging On from the Sun 35mm, ISO 100, f/1.8, 1/4000 Wide-open at macro, there is still detail to be had, though files (combined with some spherical aberration and the shallow depth of field) tend to not have any “crispness” that the lens gets when stopped down. BokehOne aspect of the 35mm f/1.8’s separation from the similar (in field-of-view) Sigma 30mm f/2.8 is the large f/1.8 aperture providing not only about 2.3 times as much maximum light but also allowing for more depth-of-field separation. However, if the out-of-focus areas are distracting, what’s the point? In general, the 35mm f/1.8 puts on a good show. For the 35mm f/1.8, far background bokeh (far left) is very smooth, especially so from f/1.8-4. Near-background bokeh (left) is smooth whenever there is any (as stopping down simply brings it into focus). Near-foreground bokeh (right) is pretty smooth wide open, but begins to distract noticeably at f/4. Surprisingly, close-foreground bokeh (far right) remains smooth all the way through f/5.6! One thing to keep in mind, these statements about bokeh usually apply to close to medium focus distances. As the focus distance increases, “far” background bokeh can be noticeably busy depending on what’s behind the subject. Tree branches, for example, can look distracting even at the wider apertures. With its supposed circular aperture (listed as a feature on the side of the box), what about the handling of out-of-focus highlights? Unfortunately, the advertised circular aperture is laughably false, with the heptagonal shape showing up already at f/4. However, highlights from f/1.8 to about f/2.5 are nice and circular, which is the area where highlights will likely show up (save for close-focus). Wide-open, highlights blend together softly, without any hard edges. At f/2.8, brighter highlights begin to show some artifacts, and borders around the highlight are slightly evident. The rings and artifacts around and in the highlights increase in visibility as the 35mm f/1.8 is stopped down further. For best highlight smoothness, stay around wide-open, but going up to f/4 still looks just fine. Farm Cat 35mm, ISO 100, f/2.2, 1/320 In this example at f/2.2, not only is bokeh very nice and smooth (rendering the straight lines of the fence softly), but most of the circular highlights have soft edges with no artifacts. Chromatic AberrationsWith its fast f/1.8 aperture, the 35mm f/1.8 has the potential to not handle chromatic aberrations very well. To test this out, I shot this worst-case scenario of branches against a sky overexposed by at least two stops: Crops taken from directly in the center Keep in mind the focus point is the branch to the right. Wide-open, there is a significant amount of both purple fringing that takes up the entire branch and green/magenta longitudinal fringing on the background and foreground braches, respectively. Already at f/2.8, however, most noticeable purple fringing is gone, and other longitudinal fringing is largely absent by comparison. Things keep on improving from then on out as the 35mm f/1.8 is stopped down, but at 100% view, the fringing is already at a negligible degree. Avoid shooting bare tree branches at or near wide-open! 🙂 Again, always remember that the above test was with the worst-case scenario. Most subjects, unless all you shoot is shaded areas on a beach or the like, will not have this much contrast to fringe. Riding Along 35mm, ISO 100, f/2.2, 1/1600 Stopped down a little, there is only a bit of purple fringing (possibly seen against the helmet straps and sky), but the discolored branches especially in the upper left of the frame are still distracting. I also tested to see if the camera’s built-in chromatic aberration correction tool helped with JPEG files. Unfortunately, I could not tell a difference between any of the above aberrations with the corrections on or off. This could be because the lens doesn’t have its own firmware for the camera yet (though, see my analysis of vignetting). FlareThe 35mm f/1.8 comes with a petal-shaped ALC-SH112 hood. I feel keeping the hood attached to its dedicated lens is a necessity, not an option, as it not only helps reduce veiling flare, but also prevents large objects (hands/corners of tables/etc.) from accidentally touching/bumping into the front element. As such, I only tested flare performance with the hood on, shot in color to show the different colors of the internal reflections: The control of flare is two-fold with the 35mm f/1.8. Flare reflections from the elements themselves, vary in intensity, visibility, and color depending on where the sun is in the frame (the two blobs seemingly dancing around each other are an effect of the optical stabilization). Simply moving a strong light source just a bit can either get rid of or introduce a lot of the flare. Keep an eye on that liveview when shooting into the sun! But WOW! Look how much contrast this lens retains when shooting into the sun! There’s not a touch of veiling flare to be found, a performance I haven’t seen in any of my old Nikkors. I guess there’s something to these modern lens coatings… 🙂 On the Corner 35mm, ISO 100, f/1.8, 1/4000 With the sun centered in the frame, some of the internal reflections vary in location depending on how the OSS is acting. (Low contrast here though due to shooting wide-open) VignettingAs an APS-C designed lens with a fast aperture, the 35mm f/1.8 is prone to heavy vignetting. Using Lightroom 4’s vignetting correction sliders, f/1.8 requires a very large +70 amount and a midpoint value of 15. At f/2.8, +35 amount is needed. By f/4, only +15 should be added. All vignetting is essentially gone at f/5.6. Though…in addition to the possible shallow depth-of-field provided at f/1.8, a little vignetting can help with subject separation. Rebel Scooter at Night 35mm, ISO 100, f/1.8, 1/15 Curiously, the vignetting-correction tool in the camera does a good job of correcting darkened corners when shooting JPEG. Why this tool works and the chromatic aberration tool doesn’t could be because vignetting characteristics are easily recognizable while chromatic aberrations are lens-specific (this is only a guess, but even the chromatic aberration removal checkbox in LR4 doesn’t remove it all). DistortionPrimes, especially “normals”, are known to have little to no distortion of geometrically straight lines in a photograph. Thankfully, the 35mm f/1.8 fits right in with the norm. I see MAYBE a slight amount of pincushion distortion, but even applying a -1 correction to the distortion slider in LR4 seems to correct too much. Sunset in the Busy City 35mm, ISO 100, f/10, 1/5 Lines, where they can be found in this photograph (street lamps, church spire, etc.), are undistorted. Seeing as there’s virtually no distortion to correct, I didn’t even bother with testing the in-camera distortion correction for JPEGs. OSS EffectivenessThe 35mm f/1.8’s arguably definitive feature is its inclusion of optical stabilization. At first thought, this could bring with it problems such as de-centering into the mix, but at least on my copy, the OSS doesn’t degrade image quality at any measurable level. The only image degradation that will happen with this lens in use is if you happen to forget to turn the OSS off when shooting on a tripod, which can sometimes be hard to remember to do. Since there is no movement for the lens to compensate for, the elements will move around themselves with long exposures, blurring images. But what about how the OSS helps in shooting? I’ve already found out how it can make handheld video nice and smooth, but testing out how it helps in the 35mm f/1.8’s calling—low-light handheld photography at super-slow shutter speeds—is crucial. After analyzing “real-world” shutter speed advantages (based entirely off of my own handholding skill) and the advantages compared to the classic 1/focal length (in 35mm terms) rule, the 35mm f/1.8’s stabilization is amazingly effective. By shooting 10-shot bursts with a brace at various settings I found my maximum reliable shutter speed without OSS (at least 7 out of 10 sharp shots) was at 1/30. By turning OSS on, that dropped all the way down to 1/4 (that’s a quarter of a second!) for a generally reliable shutter speed. That’s a solid three stops of shutter speed improvement based off of my own handholding skills! Compared to the 1/focal length rule (in which we consider the 35mm f/1.8 a 52.5mm lens), the 35mm f/1.8 provides almost FOUR stops of shutter speed advantage when OSS is on! So, let’s do some number crunching. This means that the 35mm f/1.8 can essentially allow eight times the amount of light than a non-stabilized of equal specifications (subject movement notwithstanding). So for me, instead of having to shoot the non-OSS lens at ISO 1600 at 1/60, I can easily shoot at ISO 100 at 1/4 with the 35mm f/1.8! Even compared to the E-mount kit lens, where the maximum aperture at 35mm would be around f/4.5, shooting the 35mm f/1.8 wide-open lets in about 5 times as much light. In this scenario (assuming the OSS works about as good in both lenses), a photographer can photograph moving subjects in lower-light better than the kit lens. Whereas the kit lens wide-open at 35mm would shoot at 1/10 for a shot, the 35mm f/1.8 could easily manage 1/50. Two items of note. First, the optical stabilization makes an almost inaudible whirring noise when the elements are moving (you can simulate this by shaking the camera lightly right up to your ear). The sound is inaudible in movie recordings. Second, every single photograph in this review (test shots not included), was shot handheld, just to give you an idea of the OSS’s power. Unknown Rider 35mm, ISO 100, f/4.5, 1/8 Using optically stabilized lenses allows photographers to better capture panning motion shots, where the subject looks still but the background is streaking with motion blur. I, however, have MUCH to learn to get these shots correct! Now, let’s hit the old recap. Pros and ConsPros
Cons
The Bottom LineThe 35mm f/1.8 is a fantastic lens, despite its focusing limitations dependent on CDAF. The only “real” knacks against it—heavy vignetting and noticeable fringing wide-open—can easily be worked around depending on the situation, what settings you shoot at, and how much post-processing you are used to doing. This lens truly is an all-purpose E-mount lens for excellent video and low-light photographs with shallow depth of field. Though other cheaper options exist in the general focal range for the system (the tack-sharp Sigma 30mm f/2.8 for E-mount) or other camera manufacturers (Samsung NX 30mm f/2), there’s no denying that the 35mm f/1.8 is the prime lens that a large majority of NEX photographers have been waiting for. Negative Space 35mm, ISO 100, f/1.8, 1/25 Courtyard Symmetry 35mm, ISO 100, f/1.8, 1/60 “The Look” 35mm, ISO 200, f/1.8, 1/15 Chef! 35mm, ISO 100, f/2.8, 1/6 Lamp and Spigot 35mm, ISO 400, f/1.8, 1/20 Benz 35mm, ISO 100, f/1.8, 1/4 Success! 35mm, ISO 200, f/1.8, 1/60 That’s all for this review guys and gals, thanks for dropping by! There is one piece of news I’m excited to share with you all, I have finally managed to work a photography course into my university schedule! As some may know, almost everything I have learned about photography up to now has been self-taught. I can’t wait to now go a little deeper with some “formal” training in this artform. 🙂 |